You know your car needs oil, coolant, and a variety of other fluids to run safely and efficiently. What you might not know is how often you should check these fluids to top them off, or replace them completely. Your mechanic can help you to remain up-to-date with needed fluid changes, but it never hurts to have an idea of when they're coming due.
The old rule of thumb was to change oil every three months or 3,000 miles, but in recent years, with the growing popularity of high-performance, synthetic motor oils, many drivers can now wait until they hit the 7,500-10,000-mile mark before swapping in new oil. If you're not sure what the recommendations are for your car, the best place to look is the owner's manual, although your dealer or mechanic could also advise you.
That said, no matter what type of motor oil you use or how often you replace it, you should check oil levels regularly to make sure you're not running low. Motor oil lubricates and cools moving parts, and when you're low, you run the risk of your engine overheating or even seizing. Luckily, the dipstick is usually conveniently located at the front of the engine compartment and cleverly marked to make it easy to see the current oil level (when the engine is cool).
Because brake fluid is so essential to safe operation of your vehicle (and because it can be corrosive), it is recommended that you change it every two years, at minimum. If you start to notice brakes feeling spongy or non-responsive, however, you'll want to have fluid levels checked immediately, and you may need to have the lines bled and fluid replaced.
We're not talking about the refrigerant that powers your car's AC, although it's wise to check this before summer heat sets in. Instead, coolant refers to the antifreeze fluid in your radiator that helps to cool your engine. Recommendations for changing this fluid range from three years to 30,000-60,000 miles, depending on the vehicle, but levels should definitely be checked well in advance of these benchmarks to make sure fluids aren't running low. You may want to leave this task to your mechanic, since the system is pressurized.
You might be surprised to learn that the fluid keeping your transmission lubricated could last anywhere from 60,000-100,000 miles or more, according to vehicle manufacturers, although it will depend on your vehicle and your transmission type. Of course, this could mean your fluids won't be changed for several years, if your annual mileage is moderate. You may therefore wish to adopt a preventive approach that includes changing transmission fluid at 30,000-mile intervals. It's not a bad idea to speak with a trusted dealer or mechanic if you're concerned about it.
Although fluids will require topping off or replacement at different intervals, you never want to let these measures lapse for long, as the result could be permanent damage to your engine, or even failure that results in an accident. Luckily, regular service will help you to stay on top of needed fluid changes.